Jackson has Alder body and Seymour Duncan pickups. Even though they are supposed to have the same specs, the FR's neck is fatter. Otherwise the specs on this guitar are pretty regular for a Soloist SL2H. The guitar has an alder body with a neck through maple neck. The neck on a soloist is . Jackson SL2H Pro Series Soloist Left-handed - Metallic Black image 1 . Jackson Pro Soloist SL2 Solidbody Electric Guitar at a Glance: . Tech Specs. The Jackson Soloist is an electric guitar model by Jackson Guitars officially produced since Jackson was essentially the pioneer.